Interpolymers prepared from vinyl toluene alpha methyl styrene dicyclopentadiene and optionally an acrylic compound

ABSTRACT

TERPOLYMERS ARE MADE FROM VINYL TOLUENE, ALPHA METHYL STYRENE AND DICYCLOPENTADIENE AND TETRAPOLYMERS FROM THESE MATERIALS AND ACRYLIC ACID OR METHACRYLIC ACID OR AN ALKYL ESTER OF SUCH ACIDS. THE PREFERRED POLYMERS ARE TETRAPOLYMERS INCLUDING BUTYL ACRYLATE. THE POLYMERS ARE USEFUL AS HOT MELT ADHESIVES AND HOT MELT COATINGS.

United States Patent 3,640,977 INTERPOLYMERS PREPARED FROM VINYLTOLUENE, ALPHA METHYL STYRENE DI- CYCLOPENTADIENE AND OPTIONALLY ANACRYLIC COMPOUND Carlos T. Gonzenbach, Scotia, and Manuel A. Jordan, ISchenectady, N.Y., as'signors to Schenectady Chemicals,

Inc., Schenectady, NY. No Drawing. Filed May '6, 1969, Ser. No. 822,294

. Int. Cl. C08f /40, 1/58, 17/00 U.S. Cl. 260--80.78 9 Claims ABSTRACTOF THE DISCLOSURE Terpolymers are made from vinyl toluene, alpha methylstyrene and dicyclopentadiene and tetrapolymers from these materials andacrylic acid or methacrylic acid or an alkyl ester of such acids. Thepreferred polymers are tetrapolymers including butyl acrylate. Thepolymers are useful as hot melt adhesives and hot melt coatings.

The present invention relates to novel terpolymers and tetrapolymcr s.

It is an object of the present invention to prepare novel terpolymersand tetrapolymers.

Another object is to prepare such polymers having a very low color.

An additional object is to prepare such polymers having improvedproperties compared to other polymers when used in adhesives and hotmelts.

Still further objects and the entire scope of applicability'of thepresent invention will become apparent from the detailed descriptiongiven hereinafter; it should be understood, however, that the detaileddescription and specific examples, while indicating preferredembodiments of the invention, are given by way of illustration only,since various changes and modifications within the spirit and scope ofthe invention will become apparent to thoseskilled in the art from thisdetailed description.

It has now been found that these objects can be attained by preparingterpolymers of 55-75% vinyl toluene, 520% (usually 518%) of alpha methylstyrene and l to of dicyclopentadiene. Preferably there is prepared atetrapolymer containing in addition to the three monomers specifiedabove 2 to 15% of acrylic acid or methacrylic acid or an alkyl acrylateor methacrylate having 2 to 18 carbon atoms in the alkyl group. As alkylacrylates and methacrylates there can be used, for example ethylacrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate,isobutyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate,dodecyl acrylate, dodecyl methacrylate, stearyl acryla'te and stearylmethacrylate. The preferred acrylic compounds are acrylates, mostpreferably butyl acrylate/It has been found that the use of butylacrylate moderates the exotherm in the polymerization reaction giveshigh yields or hard, light colored resins and gives superior physicalproperties to adhesives and hot melt compositions utilizing the polymer.

The polymers of the invention are water white or have a color of lessthan 1 on the Gardner scale.

The use of dicyclopentadiene in making the terpolymers and tetrapolymersgives adhesives having higher bond strengths than alpha methylstyrene-vinyl toluene copolymers.

Unless otherwise indicated all parts and percentages are byweight.

In the examples in the present case there was used either puredicyclopentad-iene or an impure dicyclopentadiene "ice calleddicyclopentadiene concentrate. Analysis of the dicyclopentadieneconcentrate was as follows:

Percent C compounds 4.0 C compounds (aliphatic) 1.0 Benzene 0.5 Ccodimers 0.2 C codimers 8.3 Dicyclopentadiene 85.6 C codimers 0.4Trimers 0.1

Contained cyclopentadiene (dicyclopentadiene plus /2 codimers) 90.0%,the C compounds were pentanes 0.7%, pentenes 1.1%, isoprene 0.9%,piperylene 1.2% and cyclopentadiene 0.1%. The specific gravity of thedicyclopentadiene concentrate was 0.92 (7.7 lbs./gal.).

Polymerization can be carried out in any convenient fashion, e.g. seeDavis Pat. 3,427,275 but is preferably carried out at 50 to 65 C. withthe aid of a Friedel- Crafts catalyst. The most preferred temperature isaround room temperature, e.g. 25-30 C. Any conventional Friedel-Craftscatalyst can be used, e.g. aluminum chloride, ferric chloride, berylliumchloride, sta-nnic chloride or the like but the preferred catalysts areboron trifiuoride in a concentration of 0.1 to 2%, preferably 0.3% ofthe total charge or titanium tetrachloride in a concentration of 0.2 to1.5%, preferably 0.5% of the total charge. The boron fluoride, forexample, can be introduced in an amount up to saturation.

The reaction is preferably carried out in an aliphatic or aromatichydrocarbon solvent or a mixture of aliphatic and aromatic solvents. Thesolvent usually is 20 to 60%, preferably 33% of the total charge. Therecan be used benzene, toluene, xylene, higher alkyl benzenes, aromaticnaphthas, aliphatic naphthanes, hexane, heptane, octane, decane,kerosene, petroleum ether, Stoddard solvent, an aliphatic solventboiling between 300 and 400 F.), mineral spirits, etc. xylene is thepreferred aromatic solvent. Unlike other solvents xylene appears to takepart in the reaction to a certain extent. The preferred aliphaticsolvent is heptane. Aliphatic solvents tend to give higher softeningpoints and lighter resin.

The reaction can be carried out by either the direct method of addition,i.e. the catalyst is added to the mixture of monomers and solvent or bythe reverse method of addition, i.e. the mixture of monomers is added tothe solvent containing the catalyst.

The reactions are typically solution polymerizations. They were carriedout in a reactor provided with a mechanical stirrer, an inert gassparge, a thermometer and a vertical water cooled condenser. An externalwater-circulating cooling bath was used to dissipate the heat ofreaction. In the preferred procedure the catalyst or monomeric mixture,as the case might be, was added to the reactor gradually maintaining thetemperature at 25-30" C. When the reaction was completed the catalystwas deactivated with a 0.06% Triton X-102 solution in water. (TritonX-102 is isooctylphenol-ethylene oxide adduct having 12 to 13oxyethylene units.) The polymerizate was then washed three times withplain water. The solvent and small portions of unreacted monomers werethen distilled at a reduced pressure of about 30 mm. to an endpoint ofabout 180 C. pot temperature or until the desired softening point of theresin was obtained. The resinous product was then decanted, allowed tocool and the physical properties determined.

In the comparison examples Piccotex and Piccotex are copolymers of about75% vinyl toluene and about 25 alpha methyl styrene prepared inaccordance 3 with Powers Pat. 3,000,868 using BF catalyst. Piccotex 100has a 100 C. softening point and PiccoteX 120 has a 120 C. softeningpoint (ball and ring) ElvaX 260 is an ethylene-vinyl acetate copolymer(28% vinyl acetate).

4 EXAMPLE 4 A mixture of an aromatic and an aliphatic hydrocarbonsolvent was used for the preparation of a resin having a softening pointof 75 C. The reaction was run by the Paisley Polymer used in the hotmelt adhesive formula- 5 tion is a commercially available amorphousatactic polyreverse method of addlhoh' propylene hydreearben, speeifiegravity Q86 at 5 F, To a 12 liter three necked flask were added 1,666grams softening point R (ball and ring) of xylene and 833 grams ofheptane. Boron trifluoride gas was bubbled through a sparge at roomtemperature EXAMPLE 1 until the solvent mixture was completelysaturated. The 0 g s Of vinyltoluene, 2,722 grams of alphafollowingmixture was added from a separatory funnel: methyl styrene, 1,452 gramsof dicyclopentadiene, 363 3,750 grams of vlnyltoluenfi, gllams of phgrams of butyl acrylate and 9 072 grams f 3 Xylene styrene, 400 grams ofredlstllled dicyclopentadiene and were loaded to a gallon stainlesssteel reactor. The 100 grams P butyl acrylate- The reactlon temperaturereactor was provided with mechanical stirrer, a condenser, 15 malqtamedat The Product Was a deal a sparge, a thermocouple and temperatureregister, and a f a Color of less than 1 f) 'f a 80ftheating and coolingjacket. The reactants were cooled to 9 8 P 0f and It Was Obtamed 1I110-20" C. and boron trifluoride was fed gradually y through the spargeuntil no more heat of reaction was EXAMPLE 5 given off (i.e. thereaction was completed). The reaction temperature was allowed toincrease to 25400 The To a 15 gallon reactor were charged 13,608 gramsof catalyst was deactivated with a 0.06% Triton X-102 in vlhyhohleh?2,722 'h of alpha'methyl Styrene 1,815 water. The polymerizate wassubsequently washed with grams ofhlcyclohehthdlehe f 9,072 g of h threeportions of water. The solvent was then removed by The reactlon was1n1t1ated with boron trifluoride following distilling it over atsubatmospheric pressures. A clear ali Procedure of Example The prodhct ha reslh h most water white crystalline resin having a ball and ring g aGardher color of 1 and a softehlhg Polht of 123 softening point of 120C. and a color less than 1 in the Yleld Gardner scale was obtained in93.1% yield. EXAMPLE 6 EXAMPLE 2 750 grams of vinyltoluene, 150 grams ofalpha-methyl The same procedure as that employed in Example 1 styrene,70 grams of dicyclopentadlene, 10 grams of diwas used to prepare a 121C. softening point resin. 12,700 vlhylbehzehe 20 grams of butyl acrylateahd 5O0 gfams grams of vinyltoluene, 3,629 grams of a1pha methy1 ofxylene were charged to a 5 liter flask provided with a rene, 1,452 gramsof dieyelopentadiene 363 grams of stirrer, thermometer, condenser and asparge. l 3F gas butyl aerylate and 9,072 grams of Xylene were reactedwas gradually addeduntll no more heat of reaction was with BF catalyst.The catalyst was added to the reactants gheh f The reachoh, temperaturewas {halhtalhed at until the reaction was completed. The product of thereac- The polymehlzate h treated as m Example tion was a clear almostwater white resin having a ball The Product was afeslh havmg a Gardnercolor of less and ring softening point of 121 C. than 1 and a softeningpoint of 122 C. (B and R). The

40 resin yield was 96.6%. EXAMPLE 3 The examples in the following Table1 were carried out The same procedure of Example 1 was again used tousing the general procedure set forth supra. The reaction prepare a veryhigh softening point resin. An aliphatic temperature was kept at about25-30 C.

TABLE I Percent Percent of total Method of S.P. Example Solvent chargeaddition V.T. M.S. DCPD B.A. M.A. Yield C.)

7 Hepatne 33 D 75 15 95.0 132 do 33 D 75 5 86.9 120 33 D 75 15 93.7 129as D 75 15 93.7 125 40 D 75 10 98.7 101 33 D 75 10 94.0 131 40 D is 98.898 50 D 10 101.1 92 50 D 75 7 102.9 89 33 D 75 15 98.0 111 33 D 75 1592.5 122 33 D 75 5 104.3 50 R 75 15 110.0 08 33 D 75 5 103.5 100 as R 7515 95.3 75

The catalyst employed was BE, and it was added until i namely heptane wused m Place of the a completion of the reaction except in Examples 19and 21 matlc solvent. The following was charged to the pilot l t t d thee ction was initiated with BF as m Whlch It was added to shun-anon P anmac or 2722 f 1 h 3 In the table, V.T. stands for vinyl toluene, M5. for13608 gramso vmy to i grafnso ap a-methyl styrene, DCPD fordicyclopentadiene (an yl styrene, 908 grams of dlcyclopentadiene, 908 gr0 70 after the DCPD indicates DCPD concentrate was used), butyl acrylateand 9 072 P hePtahe; The catalyst B.A. for butyl acrylate, M.A. formethyl methacrylate, Was added to the reactants 11nt 11 the feactlon WasD for direct method of addition and R for reverse method p The resin hada Softemng P0111t 0f of addition. All softening points were by Ball andRing. and a c01m of 1655 than 1 er scale) and it The color of the resinsproduced was 1 on the Gardner was obtained in 92.5% yield. 75 scaleexcept for Example 9 where the color was Water white, Example 13 wherethe color was 1 and Example 2 Where the color was 2. The reason foryields above 100% the manner described for the hot melt adhesives andthe results were as recorded in Table 3.

TABLE 2 Soiteniingt Adhesion (lbs. per linear inch) n Formulation Resin0.) K/K K/M K/F KIO KIV 1 Piccotex 100 100 1.7 2.5 0.6 0.2 0.3 Piccotex120 120 1.3 1.4 0.1 0.2 0.2 Example 21 75 2. 4 0. 1 0. 4 1. 6 0. 4Example 22 120 1.9 2.3 0.5 0.8 0.5 2 Picc0tex100. 100 0.2 0.8 0.3 0.20.2 Plceotex 120 120 0. 1 0. 2 0. 1 0. 1 0. 1 Example 19- 68 0.5 0.2 0.40.5 0.4 Example 21. 75 1. 5 l. 6 1. 2 0.6 O. 5 Example 80 0.8 0.3 0.30.3 Example 100 0.8 0.1 0.3 0.3 0.4 Example 18. 100 0.3 0.1 0.4 0.5 0.2Example 23- 110 0.8 0.7 0.1 0.3 0.1 Example 17 122 0.8 0.3 0.4 0.0 0.4

in a few of the examples was due to some reaction of 20 TABLE 3 thexylene solvent.

The products of the present invention were tested inAdhesm(lbs'perlmearmch) hot melt adhesive applications and compared withpic- Resin K/K K/M K/F K/C K/V cotex 10O and PI CCOtBX 120 in twodlilerent hot melt Piccmx 100 0,2 M 0.1 M 0.1 adheslve formulations.Both formulatlons were tested for giccoteir120 2.8 0.6 0.1 9.2 adhesionon kmft to kraft Paper (K/K), (2) Kraft 25 152225135311;311:1133313333:1111 ii? 31% 33? 33% to Mylar (polyethylene terephthalate film) (K/M),(3) kraft to aluminum foil (K/A), (4) kraft to cellophanelTherevasmbllmear- (K/C), and (5) kraft to vinyl film (vinyl chloridepoly- PATENTS OF INTEREST fp- 1 d Rufiing2,987,508, June 6, 1961 a wascompoSe G POWers-3,000,868, Sept. 19, 1961 El 260 g; Davis-3,427,275,Feb. 11, 1969 Arnold3,429,843, Feb. 25, 1969 Resin belng tested 50 P ffi90 What ls clalmed is:

F 2 d 35 1. A solid resinous polymer of 55 to 75% vinyl ormua Ion wascompose o toluene, 5 to 20% alpha methyl styrene, 1 to 25% of Paisleypolymer 120 dicyclopentadiene and 0 to 15 of an acrylic compound Resinbeing tested 60 selected from the group consisting of acrylic acid,meth- Micro wax 20 40 acrylic acid, an alkyl acrylate and an alkylmethacrylate Formulation 1 was prepared by melting the paraffin, addingthe resin with stirring, then adding the Elvax and continuing theheating and stirring until a homogeneous melt was obtained.

Formulation 2 was prepared by melting the resin, adding the microwax,adding the Paisley polymer with stirring after the microwax had meltedand heating and stirring was continued until a homogeneous melt wasobtained and the melt then cooled to room temperature.

The hot melt adhesive was then coated on kraft paper at 325 F., cooledand samples of the coated kraft paper placed on samples of fivedifferent uncoated substrates (kraft, Mylar, aluminum foil, cellophaneand vinyl). The pieces to be sealed (coated kraft on top) were placed ina heat sealer maintained at 225 F., for 1 second.

The sealed samples were then tested for peel adhesion at roomtemperature on the Tinius Olsen machine using the 20-pound load cell andat a rate of 2 inches per minute. The results are set forth in Table 2.

The resins were also applied in hot melt coatings. The test procedurewas identical to that set forth above. The coating formulation was:

Grams Resin to be tested 60 Paraflln 180 Microwax 100 Elvax 250(ethylene-vinyl acetate copolymer with the ethylene predominating) 60having 2 to 18 carbon atoms in the alkyl group of said acrylate ormethacrylate.

2. A terpolymer according to claim 1 consisting essentially of vinyltoluene, alpha methyl styrene and dicyclopentadiene.

3. A tetrapolymer according to claim 1 consisting essentially of 55 tovinyl toluene, 5 to 20% alpha methyl styrene, 1 to 25 dicyclopentadieneand 2 to 15% of said acrylic compound.

4. A tetrapolymer according to claim 3 wherein said acrylic compound isan alkyl acrylate.

5. A tetrapolymer according to claim 4 wherein said alkyl acrylate isbutyl acrylate.

6. A tetrapolymer according to claim 4 wherein the alpha methyl styreneis 5 to 18%, the cyclopentadiene is 5 to 25% and the alkyl acrylate is 2to 5%.

7. A tetrapolymer according to claim 6 wherein the alkyl acrylate isbutyl acrylate.

8. A tetrapolymer according to claim 7 wherein the polymer contains 75vinyl toluene, 15% alpha-methyl styrene, 8% dicyclopentadiene and 2%butyl acrylate.

9. A tetrapolymer according to claim 7 having a ball and ring softeningpoint of 68 to 131 C.

References Cited UNITED STATES PATENTS 3,427,275 2/1969 Davis et a1.2603l.8 3,487,054 12/1969 Minnerly et 21. 260-79.5 3,459,699 8/1969Levine et al 26029.7

JAMES A. SEI DLECK, Primary Examiner R. A. GAITHER, Assistant ExaminerUS. Cl. X.R.

26028.5 A, 80.8, 80.81; l17--161H

